The field of this invention relates to nuclear reactors, and more particularly to an emergency disposal system for an "out of control" nuclear reaction, this disposal system taking the form of a mass separation system which separates the larger nuclear mass into a plurality of smaller masses.
Nuclear reactors contain a plurality of fissionable material in the form of a plurality of elongated rods. Surrounding each of these rods is a control rod assembly and the nuclear reaction is controled by movement of the control rods and exposure of the fissionable material in one rod to the fissionable material in another rod. The rate of reaction is directly dependent upon the size of the mass. The more mass of fissionable material exposed, the greater the rate of reaction. If perchance an excessive amount of mass becomes exposed, what occurs is termed a "core meltdown".
A "core meltdown" is perhaps the most discussed and most feared phenomenon of all potentialities of nuclear reactors. This problem is especially of major concern since the use of nuclear reactors to produce electricity is becoming quite common. The fantastic heat generated by a molten core, estimated about six thousand degrees Farenheit, is sufficient to melt through virtually any material that might be placed in its path as it bores downward through the reactor vessel and all containments, eventually releasing at least a portion of its radioactive fission product inventory through the earth, or possibly through breaks in the containment sphere. At the present time, the use of reliable and practical methods of containing a large molten mass of fuel that would probably result from a meltdown do not exist.
At the present time, there has not been a complete meltdown of a nuclear reactor core. However, in certain instances there have been partial meltdowns which have been stopped by currently employed safety structure within the nuclear reactor. Even the occurrence of a partial meltdown has been described as a bit worse then the maximum credible accident. There is a chance that a complete meltdown would result in the fissionable material being directly exposed to the atmosphere and the pollution that would occur as a result thereof would undoubtedly be overwhelming.